Signal generation system



c. H. HOEPPNER SIGNAL GENERATION SYSTEM 1 Jan. 1949..

Filed Nov. 14, 1946 Jl l vvv vvv l AAA AAAA vvvvv AAA vvvv

R E W P mP. E H D A R N 0 C $218 {$2523 3 5a 292308 Patented Jan. 4, 1949 UNITED STATES PATENT OFFICE (Granted under the act oi March a, less, as amended April 80,1928; 370 0.0. 757) This invention relates to signal generating systems and in particular to generator systems for producing multiple pulse signal groups ln'which the individual signals are controlled in time occurrence in accordance with intelligence quanti-- ties.

In numerous applications of intelligence trans.- mission apparatus it is desired to transmit information relative to a plurality of variable quantities via a single communication link. Where intermittent response to each of the variable quantitles is satisfactory, time sharing operation such 1 as that described in the copending application Serial Number 709,629 filed November 13, 1946, titled Pulse multiplex system" of C. H. Hoeppner may be employed. An intelligence modulator is required in such apparatus totransform the variable quantities into a time sharing form which may be conveniently transmitted by a single link.

It is therefore an object of the present invention to provide a modulator system for producing a time sharing signal containing information relative to a plurality of variable quantities.

Another object of the present invention is to provide a modulator system of simple structure for producing a series of pulse signals in which individual pulses of the series are separated in time from preceding pulses of a reference series of pulses in accordance with intelligence quantities which it is desired to transmit.

Other and further objects and features of the I present invention will become apparent upon a careful consideration of the accompanying drawing and following detailed description.

The single figure of the drawing is a schematic diagrannpartly in block, of a preferred embodiment of the features of the present invention.-

In accordance with the general concepts-of the present invention, a signal generation system is provided which is capable of producing intelligence containing multiple signal groups. The system is of a simple nature permitting space..- weight, and power economies heretofore unobtainable. Operation of the system is accurately controlled in time by a stable timing device. Signals ,produced by the timing device are applied to gas filled electron tubes, all of which are normally non-conductive and may if desired be ionically heated with consequent low power requirements. In response to a firstvone of the timing signals a first one of the gas tubes is brought to conduction for a brief instant of time to produce a signalvarying substantially linearly .with time. The varying signal is supplied to a second gas tube which will be brought to conduc- 55 so thata substantially linearly rising voltage is 2 Y tion a selected interval of time after the start of telligence quantity. Subsequently, a third gas the varying signal in dependency on a first intube will be brought to conduction as a result of the action of the first tube to produce a second signal varying substantially linearly with time to permit the operation of a fourth electron tube in time dependency on a second intelligence quantity; It is therefore possible to produce signals relative to a plurality of quantities by employing an appropriate number of electron tubes. Where all of the signals thus produced are to be transmitted via a single channel, they may be combined in a conventional manner. with particular reference to the figure, .a typical intelligence modulation system is shown which may be timed in operation by a sinusoidal oscillation signal generator II. From these sinu-- soidal signals, a series of pulse type signals of short duration are derived'by the pulse former l'l Short duration impulses thus produced are appliedin parallel to grids l2, l3, Id of gas filled primary electron tubes l5, l8, II. The electron tubes i5, II, I! are preferably of the tetrode' variety in which the initiation of the conductive condition is dependent upon the voltages applied to two control elements or grids. In the steady state, tubes l8, l6 and H 'are non-conductive and hence do not require anode circuit power. This non-conductive condition is maintained by. a

negative voltage supplied to theg'rids l2, l3, l4

' 25 are of sufilcient magnitude so that either,

alone, can prevent conduction within. the tubes IL". H. In other words, positive signals must be simultaneously supplied to the two grids of each tube to initiate conduction therein. Also a suflcient voltage diiferential must be present between anode and cathode to sustain conduction.

Disposed in the anode circuit of each of the primary tubes l5, l8, I1 is a time constant circuit typified in the case of tube It by the resistance 28 and capacitance 21. This time constant circuit serves to limit the duration of the conduc-- tive condition within tube II. In the cathode circuit of each primary tube is a time constant circuit typified for tube I! by the resistance capacitance combination i9, 28. Conduction by tube li produces a charging of capacitance 28 gaseous secondary electron tube 30 which'is nor- 1 mally maintained non-conductive by virtueoi a negative biasing voltage supplied across terminals 3|. The rising signal applied to grid 29 is imopposition to the average biasing voltage from terminals 3|. The exact point in the cycle of rising grid voltage at which tube 30 becomes 1 conductive may be and is varied at will by adlusting the position of the tap on the potentiometer 32 or by varying the magnitude of the voltage impressed between terminals 3|. By this 'means then, it is possible to control the time displacement between the initiation of conduction in tubes and in accordance with the posltion of a shaft, as by the movable contact on' potentiometer 32, or by a varying voltage signal applied to terminals 3 l.

Termination of conduction in tube 30 is provided by the resistance-capacitance network 333-4 placed in the anode circuit thereof. Conduction by tube 30 removes more chargefrom capacitance 34 than can be supplied by resistance 33 so that the capacitance discharges, lowering the voltage impressed across the tube. Eventually this voltage falls to a level 'at which conduction by tube 30 cannot be maintained. Conduction then ceases and the tube becomes inoperative.

Upon the initiation of conduction in tube 30, a sharp voltage change occurs across the cathode resistance 35. This voltage change is applied through the coupling capacitance 36 to an output terminal 31. In certain applications it may be desirable to employ a small value of capacitance for element 36 to obtain a differentiating action.

The varying signal fromthe cathode of tube I5 is also supplied to the grid 23 of tube H3. The signals supplied to grid i3 are not of suflicient amplitude to, alone, cause the initiation of conduction in tube 16, however, when supplemented by the rising voltage from the cathode of tube IS a pulse signal from former II can cause the initiation of conduction. Tube l6 may then be employed to permit the subsequent initiation of conduction in tube 38 in accordance with a. signal obtained from potentiometer 39 and the initiation of conduction in tube II in accordance with a'subsequent signal from pulse former ll.

Primary tube I! operates in a manner similar to tubes l5 and I6, however, the changing voltage obtained at the cathode thereof is applied to the grid 22 oftube l5 through capacitance I 40 and resistance 4| so that conduction by tube i5 can be initiated again by a subsequent pulse from former II to continue the operation of the primary tube chain.

It is apparent that any desired number of pri-' mary tubes may be inserted between the tubes l5 and I! to control operation for any number of variable quantities. ing number of secondary tubes 30, 28, etc., would be required.-

When the equipment is first turned on, the initiation of the conductive condition in tube l5 In such case a correspondthebiasing voltage for grid 22. Such bias reduction may be effected by a momentar grounding of the junction between resistance 4i and capacitance 40, as by switch 42, until the cyclic operation is started.

From the foregoing discussion it is apparent that considerable modification of the features of the present invention is possible and while the device here shown and. described and the form of apparatus for the operation thereof constitutes a preferred embodiment of the invention it is to be understood that the present invention is not limited to this precise device and form of'apparatus and that changes may be' made therein without departing from the scope of the invention which is defined in the appended claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

' What is claimed is:

1. A signal generator device for producing a series of intelligence conveying pulse type signals in which each of the signals is individually spaced from a preceding reference signal in accordance with intelligence to be conveyed, comprising; means producing a series of accurately spaced timing signals, individual primary gaseous electron tubes for each intelligence quantity to be conveyed, means interconnecting the primary electron tubes in a tandem manner so that one tube may be controlled in operation by a preceding tube of the tandem in accordance with the timing signals, enablingmeanspermitting initiation of conduction in a primary electron tube for a first quantity in accordance with a first timing signal, individual secondary gaseous electron tube means for each intelligence quantity to be conveyed, separate integrator means connecting each of said secondary tubes to a corresponding primary tube, said last named means being operative to render each of said secondary tubes conductive in response to the establishment of conduction in the corresponding primary tube but time delayed therefrom, the time delay being in duration dependency on the corresponding intelligence quantity to be conveyed, a common output channel, and means delivering a signal into the common output channel in response to a change in conductivity conditions of. the secondary electron tubes.

2. A signal generator device for producing a series of pulse type signals individually spaced from a preceding signal of a reference signal train ingaccordance with intelligence to be transmitted, comprising; means producing a series of accurately spaced timing signals, a first soft tube electron tube means responsive to a first reference signal of the train to cause the production of a first keying signal varying in amplitude substantially linearly with time over a portion thereof, a second soft tube electron tube means responsive to the first keying signal and a first intelligence quantity to change conductivityconditions in interval of time after the first timing signal in dependency on a first intelligence quantity, a third soft tube electron tube means responsive to a second timing signal of the train toproduce a second keying signal having linear amplitude variation with time, a fourth soft tube electron tube means responsive to the second keying signal and to a second intelligence quanmay be facilitated by a momentary reduction in 7 tity to change conductivity conditions an interseries of pulse type signals individually spaced from'a preceding signal of a reference signal train in accordance with intelligence to be transmitted, comprising; means producing a series of accurately spaced timing signals, a first soft tube electron tube means responsive to a first timing signal to cause the production of a first keying signal varying in amplitude substantially linearly with time over-a portion thereof, a second soft tube electron tube means responsive to the first keying signal and a first intelligence quantity to change conductivity conditions an interval of time after the first timing signal in dependency.

on the firstintelligence quantity, a third soft tube electron tube means biased in part by the I first electron tube means responsive to a second timing signal of the train to cause the production of a second keying signal having linear amplitude variation, a fourth soft tube electron tube means responsive to the second keying sig-- nal and a second intelligence quantity to change conductivity conditions an interval of time after the second timing signal .in dependency on 'a second intelligence quantity, means deriving output signals in a fixed time relationship to the change in conductivity conditions of the second and fourth electron tubes, and additional electron tube means for producing additional output signals in accordance with additional intelligence quantities to be conveyed.

A. A signal generator device for producing a series of pulse type signals individually spaced from a preceding signal of a reference signal train in accordance with intelligence to be transmitted, comprising; means producing a series of accurately spaced timing signals, a first soft tube electron tube means responsive to a first timing signal of the train to produce a. current surge and to cause the production of a first keying signal varying in amplitude substantially linearly with time over a portion thereof, a second soft tube electron tube means responsive to the first keying signal and a first intelligence quantity-to change conductivity conditions an interval of time after the first-reference signal in depend ency on the first intelligence quantity, an energy storage circuit, a series resonant inductancecapacitance circuit connected to an electrode ofthe first electron tube to produce an enabling signal in response to the current surge produced thereby, a third soft tube electron tube means responsive to the enabling signal and to the timing signalsto produce a third current surge when a second timing signal and the first positive crest of the enabling signal bear selected amplitude relationships, means producing a second keying signal having linear amplitude variatidn in response to the third current surge, a fourth soft tube electron tube means responsive to the second keying signal and to a second intelligence quantity to change conductivity conditions an interval of time after the second timing signal in dependency on a second intelligence quantity, means deriving output signals in a fixed time relationship to the change in conductivity conditions of the second and fourth electron tubes, and additional electron tube means for producing additional output signals in accordance withadditional intelligence quantities to be conveyed.

5. A signal generator device for producing a series of pulse type signals individually spaced from a preceding signal of a reference signal train in accordance with intelligence quantities to be transmitted, comprising; means producing a series of accurately spaced timing signals, a first soft tube electron tube means responsive to a first timing signal of the train to initiate a current surge and cause the production of a first keying signal varying in amplitude substantially linearly with time over a portion'thereof, means terminating the current surge in the first tube after a predetermined duration thereof, a second soft tube electron tube means responsive to the first keying signal and a first intelligence quantity to initiate a second. current surge an dependency on the first intelligence quantity,

means terminating the current surge in the second tube after a predetermined duration thereof,

an energy storage circuit connected to the cathode of the first electron tube to produce an enabling signal in response to the current surge produced thereby, a third soft tube electron tube means responsive to the enabling-signal and to the timing signals to initiate a third current;

surge when a second timing signal and the enabling signal bear selected amplitude relation- 1 ships. means terminating the third current surge after a predetermined duration thereof, means producing a second keying signal having linear amplitude variation in response to the third cur-- rent situ'ge,- a fourth soft tube electron tube means responsive to a second keying signal and a second intelligence quantity to initiate a fourth current surge an interval of time after a second timing signal in dependency on a second intelligence quantity,- means terminating the current surge in the fourth tube after a predetermined duration thereof, and additional electron tube means for producing additional output signals in accordance with additional intelligence quantities to be conveyed. a

CONRAD H. HOEPPNER.

REFERENCES CITED UNITED STATES PATENTS Date Number 7 Name 2,092,887 Luck Sept. 14, 1937 2,409,229 Smith et al. Oct. 15, 1946 

